Traditionally, clam-shell and stack-up cylindrical motor housings have been used to enclose electric motors for power tools. Clam-shell motor housings include two semi-cylindrical halves which are joined together along planes which are colinear with the longitudinal axes of the cylindrical housings. In contrast, the stack-up motor housings split apart along planes perpendicular to the longitudinal axes of the cylindrical housings and use cylinders with end caps to enclose the motors.
Each of these types of housing generally have threaded mounting apertures for receiving fasteners which attach brush holder assemblies to the housings. Due to their particular geometric configuration and method of manufacture, the mounting apertures in the clam-shell motor housings typically have axes which extend perpendicular to the longitudinal axes of their cylindrical housings. The axes of mounting apertures in stack-up motor housings generally extend parallel to the longitudinal axis of the housings. Accordingly, different configurations of brush holder assemblies are needed to mount to the mounting apertures in these different types of motor housings while still properly positioning brushes secured in the holder assemblies in proper alignment with a commutator of a motor.
The present invention is intended to overcome the problem of having to manufacture separate brush holder assemblies for use with each type of clam-shell or stack-up motor housing.